SPHK2 and lung carcinoma: FTY720 (Fingolimod/Gilenya, Novartis, Basel, Switzerland) is a sphingosine analogue drug that is phosphorylated by SphK2 to produce a structural analogue of S1P and functional antagonist for S1PR1 that acts a tumor suppressor in colon and lung cancer cell lines and mouse models [45,46,47,48].